I'm not on the Mirena but will be considering it or the Copper IUD in the next few months-year. I'm doing my research between the two and would like to know if weight side effects happen with the Mirena (altho the hormones in it are only suppose to effect the uterus).
However, I did stop BCP a week ago. I just wasn't noticing any weight loss; just maintenance from the weight I was when I started the pill 8 months ago. Granted, my diet/exercise isn't that strict right now (still trying to get into the habit of things) but it isn't really different from before when I first started the pill. I was able to lose weight at a slow pace. So I do believe the pill had some factor of me not being able to get below 190. So, I ditched the pill. It's only been a week and I want to try 3-6months of being medication free to see if the pill did have any factor in it. Hence, I don't want to insert an IUD right now in case there is some side effect of weight gain/maintenance which is one of the reasons why I went off the pill. I guess this is all my little experiment

It's hard to be 100% motivated/strict with diet and exercise when you see little results.